This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What is the most important information I should know about verapamil?

You should not use verapamil if you are allergic to it, or if you have certain serious heart conditions such as "sick sinus syndrome" or "AV block" (unless you have a pacemaker), low blood pressure, or if you have recently had a heart attack.

Before taking verapamil, tell your doctor if you are allergic to any drugs, or if you have kidney disease, liver disease, congestive heart failure, or a nerve-muscle disorder such as myasthenia gravis or muscular dystrophy.

There are many other drugs that can interact with verapamil. Tell your doctor about all medications you use. This includes prescription, over-the-counter, vitamin, and herbal products. Do not start a new medication without telling your doctor. Keep a list of all your medicines and show it to any healthcare provider who treats you.

Verapamil may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be alert.

Do not stop taking this medication without first talking to your doctor. If you stop taking verapamil suddenly, your condition may become worse.

Verapamil may be only part of a complete program of treatment that also includes diet, exercise, and other medications. Follow your diet, medication, and exercise routines very closely.

If you are being treated for high blood pressure, keep using this medication even if you feel well. High blood pressure often has no symptoms. You may need to use blood pressure medication for the rest of your life.